1. Field of the Invention
The present invention concerns a continuous, on-board harvest weighing device and process for various agricultural products which may be in the form of grains (cereals and others), or seeds (coffee, beans, etc.), or berries (grapes, raspberries, gooseberries, currants, etc.), or others (olives, walnuts, almonds, tomatoes, etc.).
2. Description of Background and Relevant Information
It also concerns harvesting machines for various agricultural products making use of this device and this process.
In general, continuous, on-board weighing on harvest machines is intended to offer growers the possibility of determining, in real time, the per-hectare yield of their cultivated land parcels and to establish parcel maps for use in the selection of crops and/or in land conditioning.
The device and process according to the invention are very advantageously applicable for continuous, on-board harvest weighing of berries such as grapes, raspberries, gooseberries, currants, etc., such that this application is described more specifically in the following as an absolutely nonrestrictive example.
For example, in the area of viticulture, it is known that the production of quality wines (wines with a guarantee of origin) requires winegrowers, at the time of harvest, not to exceed the per-hectare yields established by regulations based on the quality certifications.
On the other hand, it is known that worldwide viticulture and especially French viticulture are more and more oriented toward quality production.
To meet this objective, it is necessary to proceed with selective grape harvesting according to which only grapes with the required qualities of maturity are harvested. Currently, such selective harvests are performed manually. However, the applicant has perfected a machine and a process for selective harvesting of grapes, using a known shaking system, comprising two superimposed grape picking units, and coupled with at least one electrohydraulic drive device including at least one hydraulic cylinder controlled by a servovalve driven by a electronic control unit with a microprocessor.
However, even if one masters the laws of movements of the shakers or picking arms, it is indispensable, to arrive at a selective harvest with the best yield authorized by the regulations applicable to the quality zone in question, to determine, in real time, the weight of grapes harvested.
The continuous weighing tests performed with known devices and processes have enabled verification of the fact that it is not possible to extrapolate the continuous per-hectare yield measurement system from combines, because the products in question are completely different (since the grape harvest is partially liquid). On the other hand, another major difficulty for continuous harvest weighing on a grape harvesting machine, during operation, results from the magnitude of the interference with weighing due to the vibration of the harvesting head and the tilting of the machine on hills, slopes, and banking when it operates on irregular terrain.
The object of the invention is thus a process and a device for continuous, on-board weighing in real time of the harvested material enabling overcoming the aforementioned causes likely to distort the weighing and obtaining the best possible precision.
A machine and a process are known (WO89/03023A) for weighing using two electronic balances placed on the same support and connected to an electronic computer, with one of these balances being a control balance supporting a fixed known reference mass, whereas the second balance supports a weighing platform, with electronic computer being programmed to process signals originating from the two balances, in order to eliminate the effect of the dynamic interference to which these balances may be subjected. The process and the machine described in the aforementioned document do not enable performance of the very specific weighing which is continuous weighing on a harvest machine such as a grape harvesting machine.
A weighing machine (EP 0 656 530 A) is also known which includes a weighing platform consisting of a belt-type conveyor of which the carrying structure rests on a plurality of weighing cells disposed on the floor, with this machine also including vibration detection cells disposed on the floor to detect vibrations thereof and to issue detection signals, and a signal processing unit enabling processing of signals from the weighing cells and the vibration detection cells, to correct the effects of the vibrations of the floor on the weight signals. This machine does not use a pair of balances constituting one balance with a weighing platform and a control balance with a known fixed reference mass. Nor does it use means to provide for the continuous passage of a harvested material over the weighing platform of a second balance positioned stationarily in the path of the harvested material or an electronic computer programmed to perform, during weighing, algorithmic processing of the signals from the two balances, to eliminate the effect of the dynamic interference to which these balances are subjected.
Neither the machine disclosed in the document WO 89/03023 nor that described in the document EP-0,656,530A is usable to perform weighing, continuously or in successive lots, on harvesting machines, of very specific semisolid, semiliquid harvested products, such as grape harvesting.